It is often difficult to construct roads and/or buildings on wet subgrades. Specifically, wet, saturated soils, clays, and other ground materials often pose problems where construction is to occur. A wet subgrade may cause delays as it is often difficult if not impossible to pass heavy construction machinery over the wet subgrade without the machinery becoming entrenched or other stuck. Oftentimes, even if machinery does not become entrenched, deep ruts may be cut into the ground and these ruts may fill with water, making it ever more difficult to pass heavy machinery thereover.
Wet subgrades may be particularly difficult to work with in climes or seasons with heavy rainfall. In many cases, construction projects are often delayed due to wet subgrades and inability to traverse the necessary heavy machinery over saturated grounds. In any construction project, roads are often first to be constructed, as construction cannot occur if heavy machinery cannot pass from one location to another necessary location to complete the construction project. Thus, in many parts of the world, construction projects are done only in dry seasons, or at times with minimal rainfall. Therefore, wet subgrades can significantly increase the cost and extend times of completion of construction projects.
To aid in allowing heavy machinery to pass over wet subgrades, the soil in the wet subgrades may be modified and/or stabilized. Soil modification and stabilization typically involves spreading mineral material, such as, for example, cement powder, fly ash, lime, any other cementitious material, or a combination thereof, onto the wet subgrades to provide a working platform for access and construction equipment. The material is typically spread over the top of the wet subgrade, and subsequently mixed with the saturated soils and clays with a reclaimer. The mixed subgrade is then flattened thereby providing a relatively dry and stable base. The relatively dry and stable base has reduced plasticity and improved compaction, allowing heavy machinery to pass thereover without risk of entrenchment or creating difficult to pass ruts.
One problem facing the industry of soil modification/stabilization is that the aforementioned heavy machinery is typically necessary to pass over wet subgrades to spread the soil modification material. However, without the soil modification, the heavy machinery used to spread the mineral material can itself become entrenched. Moreover, large ruts left in wet subgrades by typical soil modification trucks may make it difficult for later mixing and/or flattening thereby making it difficult for heavy machinery and equipment to pass thereover, even after the soil has been modified and stabilized.
A need, therefore, exists for an improved soil modification apparatus. Specifically, a need exists for an improved soil modification apparatus that does not itself become stuck or entrenched in wet subgrades before it can spread soil modifying mineral material thereon. More specifically, a need exists for an improved soil modification apparatus that minimizes the formation of deep ruts or trenches that may make it difficult for subsequently heavy machinery and equipment to pass thereover.
Typically, soil modification apparatuses are large, heavy machines having a bin or hopper on a rear thereof, a cab, and a set of wheels for maneuvering over the wet subgrade. FIG. 1 illustrates an exemplary prior art soil modification apparatus 10. The soil modification apparatus 10 is typically a truck having a cab 12, a bed 14, a bin or hopper 16. The bin or hopper 16 is typically loaded with soil modification material configured to be utilized to modify and stabilize wet subgrades, and is typically spread from a rear of the truck via a spreader 18. Internal machinery, such as one or more augers internal to the bin or hopper and the spreader move the soil modification material from the bin or hopper to the spreader, thereby spreading the soil modification material onto the wet subgrade.
The soil modification apparatus 10 may further typically have a plurality of wheels 20 on the cab 12 and the bed 14 for moving the truck over the wet subgrades. The wheels 20 often become entrenched in the saturated ground or cause deep ruts or trenches to be formed. A need, therefore, exists for an improved soil modification apparatus that eliminates wheels for improved traction of the same.
Moreover, to minimize the effect the wheels may have on wet subgrades, the bins or hoppers may be only partially filled with soil modification material, as the weight of the soil modification material may exacerbate the entrenchment of the wheels or cutting of deep ruts and trenches into the saturated ground. As such, soil modification material must constantly be replenished, delaying completion of the soil modification project.
A need, therefore, further exists for an improved soil modification apparatus that may utilize a relatively larger bin or hopper thereon. Moreover, a need exists for an improved soil modification apparatus that may fill its bin or hopper to its maximum capacity, thereby minimizing stoppages for refilling during use thereof.